Combining irbesartan and trichlormethiazide enhances blood pressure reduction via inhibition of sympathetic activity without adverse effects on metabolism in hypertensive rats with metabolic syndrome.

Sympathoexcitation and oxidative stress in the brain have pivotal roles in hypertension with metabolic syndrome (MetS). Here, we examined whether oral administration of irbesartan (IRB) and trichlormethiazide (TCM) decreases blood pressure (BP) via inhibiting sympathetic activity through anti-oxidant effects in the brain of spontaneously hypertensive rats (SHR-cp). IRB/TCM treatment decreased BP more profoundly than IRB monotherapy. Urinary norepinephrine excretion and oxidative stress in the brain were decreased in both IRB and IRB/TCM groups without any adverse effect on the metabolic profile. These findings suggest that IRB/TCM profoundly decreases BP in SHR-cp by inhibiting sympathetic activity via anti-oxidant effects in the brain.